CH controlled by thermostat even when programmer off | Central Heating Forum | Plumbers Forums

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Discuss CH controlled by thermostat even when programmer off in the Central Heating Forum area at Plumbers Forums

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I've just noticed that with the CH programmer either selected off or timed off, the CH can still be controlled on/off at the room thermostat.
HW is controlled by the same programmer and is operating normally.
System is a pumped Y plan.
I take it the programmer is fubar?
Anything I can do to confirm or is it obvious the programmer is at fault; it's a Drayton Tempus 7.
 
The pic is of my programmer backplate.
1=HW off; 3=HW on; 4=CH on
With the programmer fitted and CH selected off I'm getting 240v at wire 4 in the junction box; I take it this indicates a fault in the programmer, with no wire to CH off at the backplate is the CH controlled by voltage at 4 @240v for CH on and 0v CH off?
 

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It does seem like the programmer and it doesn’t need a CH off, just HW off, which you have. Shouldn’t be getting 240vac at number 4 in junction box if that’s for the room stat.
 
Have you checked to make sure you’re not getting 240v at terminal 4 of the mounting plate with the programmer removed.

Just to make sure something else isn’t potentially wired wrong.

Also the mounting plate Earth isn’t connected.
Thx Tim, good call; I checked it and there's no voltage at the back plate on t4, which confirms the programmer at fault.
I noticed the earth not connected, I'll sort that when I fit the new programmers back plate.
 

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